NEW YORK » When A. Alfred Taubman, the chairman of Sotheby’s, was convicted of leading a price-fixing scheme with Christie’s and sent to prison in 2002, the scandal rocked the elite auction world and reverberated throughout Manhattan. He left under a cloud.

What a difference a few years (and $500 million worth of connoisseur art) make.

Now, Sotheby’s is celebrating Taubman — who died in April at 91 — pulling out all the stops to promote the sale, beginning on Nov. 4, of his extensive art collection, from old masters like Raphael to 20th-century masterworks by Modigliani, Matisse, Picasso, Schiele and de Kooning.

Sotheby’s plan to augment its own fortunes depends, in part, on whether it can resurrect a positive image of Taubman that today’s public may not recall: that of a legacy collector, an esteemed patron, and, as the catalog calls him, "an American gentleman."

"This is a historic sale," said Simon Shaw, Sotheby’s co-head of Impressionist and modern art worldwide. "There has never been a collection of this significance."

Sotheby’s marketing efforts include a custom-printed banner around its Upper East Side headquarters featuring images of artworks in the collection as part of the presale exhibition, which opens on Saturday.

It has redesigned the 10th-floor exhibition space to evoke Taubman’s Bauhaus aesthetic. The glossy, 400-page catalog, with essays by the cosmetics tycoon Leonard A. Lauder and the retail executive Leslie Wexner, and a biographical online video featuring Henry Kissinger, are reminders of how much is riding on the auction.

Not only did Sotheby’s fight hard to win the sale away from its archrival Christie’s (finally succeeding after several months’ effort in September), but it fully guaranteed the sale for $500 million to the Taubman family. Sotheby’s declined to say whether it has been able to share some of that financial commitment with third-party guarantors.

Sotheby’s hopes the sale, which includes more than 500 pieces spread across four dedicated auctions, ranks among the biggest, like Christie’s $477 million Yves Saint Laurent sale in 2009, particularly since it has been losing ground to Christie’s in postwar and contemporary art.

Moreover, the sale represents the first real test for Sotheby’s president and chief executive, Tad Smith, who took over in March (promising shareholders that he would make judicious use of guarantees to sellers).

The stakes are also high for the Taubman family, which not only wants to make as much as possible (proceeds will go toward estate taxes and a private foundation), but to affirm its patriarch’s legacy as a respected collector.

"If I could dream of anything out of the auction, it is that one day they’ll talk about Taubman as a provenance — the way we talk about Thannhauser or Havemeyer or Gould," said Taubman’s son William Taubman, 56, in a recent interview at the auction house. "That would be a great tribute to my father."

Some collectors and dealers say the collection has been overhyped, that Taubman often bought pieces at the low estimate that would not otherwise have sold — partly as a favor to Sotheby’s specialists who asked for his help.

But Smith said Sotheby’s did not overpay, nor is it excessively exposed in having guaranteed the sale.

"Would I have preferred a lesser guarantee at the same profit level? Sure," he said. "Am I comfortable that what we did was a good decision for the shareholder? Yes. Am I confident that we’ll make a profit? No. I can’t forecast the art market."

And others say A. Alfred Taubman chose well over his more than 60 years of amassing pieces by artists ranging from Dalí to Degas.

"The quality of the collection is outstanding," said James Corcoran, the longtime Los Angeles dealer who sold several pieces to Taubman. "It’s going to make the mark for this year — to decide how strong the art market is."

Among the highlights of the collection are two Rothkos (each estimated at $20 million to $30 million), a de Kooning ($25 million to $35 million) and four Picassos (one of which is estimated at $25 million to $35 million).

"There’s a very good Toulouse-Lautrec," said Lucy Mitchell-Innes, a dealer who once worked under Taubman at Sotheby’s, adding that Taubman collected work that "wasn’t necessarily the prettiest or the easiest."

She also called out the Modigliani, "Paulette Jourdain" — which Shaw described as "everything one wants from one of these late pictures" — which is expected to bring more than $25 million. (Christie’s is also selling a Modigliani this fall, estimated at $100 million.)

"There are plenty of pictures he fought for," said Christopher Apostle, Sotheby’s director of old master paintings, citing as an example Jacopo Ligozzi’s "Abduction of the Sabine Women" (now estimated at $600,000 to $800,000), which Taubman bought in 1990 for $396,000 (above the high estimate).

Most of these pieces have not been seen for years, having been in Taubman’s residences (in Bloomfield Hills, Michigan; Palm Beach, Florida; Southampton, New York; and New York City).

During his 22 years as Sotheby’s principal owner, Taubman, a shopping mall magnate, transformed the auction business from one directed at dealers and gallerists to one that directly targeted collectors. "More than any other single figure, he created today’s auction market," Shaw said.

Sotheby’s became publicly traded under Taubman, who sold his controlling stake in 2005, but continued to attend the auction house’s sales and exhibitions.

His long history with Sotheby’s would make the auction house seem like the obvious resting place for Taubman’s collection — particularly since his son Robert Taubman is on the board and his stepdaughter, Tiffany Dubin, works there as a vice president.

But the Taubman family made Sotheby’s work to win the sale, an approach that William Taubman said his father would have supported.

"What he would want is the best job and the best overall deal," he said. "I think, at the end of the day, we got that at Sotheby’s."

He added that his brother Robert Taubman recused himself from the decision-making process because he is a Sotheby’s director.

"My brother was uninvolved," William Taubman said. "He did not know which direction we’d gone in until after the decision had been made."

Smith said the sale was worth fighting for and he was comfortable with having had to compete for it.

"We thought it was very important to our shareholders to have it," he said.

William Taubman and other family members (including William Taubman’s wife, Ellen, and sister Gayle Taubman Kalisman) have been involved in every detail of the sale, from the font for the graphics to the paint color of the exhibition walls.

The elder Taubman did not collect along thematic lines, William Taubman said, although there are some consistencies.

"My father loved faces," William Taubman said, "whether Schiele or Modigliani or Bacon" — and geometric pieces, all of which he mixed together in his homes.

The auction house has tried to recreate the feeling of the Taubman home in designing its exhibition, giving the rooms domestic scale — in particular one meant to feel like a Park Avenue living room — "so they can understand just how it’s going to look in their homes," William Taubman said.

Visitors will view Frank Stella’s geometric painting through a Henry Moore sculpture, for example, "the way you did in my father’s house," William Taubman said.

A. Alfred Taubman made his fortune owning real estate, A&W root beer, movie theaters, department stores and malls. Trained as an architect, he had a sharp aesthetic eye, William Taubman said, starting to collect in the 1950s and buying contemporary art before it was in vogue — Morris Louis, Andy Warhol and Franz Kline.

Seemingly far from peoples’ minds, Sotheby’s hopes, will be A. Alfred Taubman’s history as someone who served nearly 10 months in prison. (Christie’s chief executive, Christopher M. Davidge, won amnesty from prosecution; its former chairman, Anthony Tennant, who was charged with Taubman, never stood trial.)

Ultimately, William Taubman said, the sale represents the taste of one man who bought what he liked and wanted to live with — and who sold things rarely.

"It’s a collection my father put together," he said. "What you see is the personal collection of an individual."